Cloverleaf seems to be the more modern name for this antenna. I believe that originally it was called the Skew Planar Wheel Antenna. I think originally Cloverleaf was the name coined for antennas with only 3 elements whereas the Skew-planar had , but the terms seem interchangeable now. This is the earliest reference i can find. http://www.slvrc.org/902band/skewplanar.htm